Those sound migraine-ish, though they could be other things. I've had the flashes of steel-spike-rammed-through-my-skull type pain, but for me it's rare and only lasts 5 minutes or so (thank god). Migraines sometimes have an "aura" (<-- actual medial term) where you see shimmery, jagged patterns that slowly go away. I get "silent" migraines (where I get the visual effects but no pain) and I lose most of my visual field for about 45 minutes.
Anyway, a doctor could help to figure out if it's something dangerous, and if it isn''t and is just migraines there are meds that can sometimes help to prevent them. And also, I've heard of people being totally incapacitated by pain from migraines and needing to go to the ER and get heavy-duty pain killers like demerol (but it can be risky because ER doctors can't physically test for migraines, so they tend to suspect you're faking it to get drugs). So, they can be as painful as you're describing.
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Aspie Quiz: 160/43
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